Packaging box with closure flap lock

ABSTRACT

A packaging box has four side walls and at least one closure flap that is pivotably joined to one side wall. The packaging box has a tuck-in tab, which can be introduced in the vicinity of the opposite side wall into an inner chamber of the box. The packaging box has an inner partition parallel to two of the side walls. A hook-like projection is provided on the partition. Upon the introduction of the tuck-in tab into the inner chamber during the closing of the closure flap, the hook-like projection automatically engages a through opening in the tuck-in tab and thereafter keeps the closure flap firmly in the closed state.

RELATED APPLICATION DATA

This patent is related to and claims priority benefit of German Patent Application DE 10 2017 000 123.5 filed Jan. 9, 2017. The entire content of this prior filed German application is hereby incorporated herein by reference.

BACKGROUND

The disclosure relates to a packaging box made from a folded cardboard blank, and in particular to a box which can be folded flat for shipping or storage and can be erected for use. The disclosure relates in particular to a box that can be torn open serving as a package for nachos and at least one dip or sauce cup.

Cardboard boxes for use as packaging, with two first and two second side walls, spaced apart in pairs from one another and facing one another at a distance on opposed first and second sides of the box, and with at least one closure flap, defined by the first and second side walls on a third side of the box, that in a closed state closes an inner chamber, are well known. As a rule, the closure flap is pivotably joined to a side wall along a fold line, and on the other side it is provided with a tuck-in tab, which can be introduced into the inner chamber of the box in the vicinity of the opposite side wall in order to keep the closure flap closed.

Several possibilities exist for preventing unwanted opening of the closure flap. If the closure flap is mounted on one of the first side walls, then one known possibility is to provide each of the two second side walls with a projecting tab, and these tabs, before the closure flap is closed, are folded under the closure flap from opposite sides. The tabs are provided with small projections on their peripheral edges that face away from the closure flap; the projections, after the closure of the closure flap, each catch in respective opposed notches on the opposed ends of a fold line that is located between the tuck-in tab and the closure flap. This type of locking is virtually invisible, and thus it does not impair the aesthetic appearance of the box. However, if the contents of the box have a certain weight and press from inside on the downward-pointing closure flap, it can happen that the projections emerge from the notches, which is unwanted, and that the closure flap opens, and as a result the contents fall out of the box.

Another possibility is to secure the closure flap with an additional locking tab, which is stamped out of the side wall adjacent to the tuck-in tab and is pivotably joined to that side wall. After the closure of the closure flap, the locking tab can be partly inserted into a slot opening in the closure flap in order to secure the latter, as shown for example in FIG. 3 of DE 20 2008 001 304 U1. In this version, it is seen as disadvantageous that first, the locking tab impairs the aesthetic appearance of the box, and second, that after the closure of the closure flap, upon the introduction of the locking tab into the slot opening, one additional step or action is needed.

Boxes comprising a folded blank of cardboard that in addition to at least one closure flap also have an inner partition are known for instance from U.S. Pat. No. 3,186,622 A, U.S. Pat. No. 2,569,018 A, DE 44 08 680 A1, and DE 20 2005 008 003 U1; the last three of these disclose a box of the type defined at the outset.

Boxes of this kind can be used for example as packaging for nachos or nacho chips that, along with one or more dips or sauces, are meant to be eaten in movie theaters or at large public events. Expediently, these packages are shipped and stored flat and then, before being sold, they can be erected and filled with the nachos or nacho chips as well as one or two dip or sauce cups and then closed by closure of the closure flap, or of one of the two closure flaps. The upper side wall of these packages has a portion that can be torn open so that the customer can remove the nachos and the dip or sauce cups without having to re-open the closure flap, or one of the closure flaps. Furthermore, the upper side wall can be provided with one or two stamped-out openings for inserting the dip or sauce cups, for example as in the box in DE 20 2005 008 003 U1, so the dip or sauce cups need not be held in the hand during consumption. The inner partition, together with one of the two second side walls, serves to brace the upper side wall on either side of the stamped-out openings, so that the dip or sauce cups inserted into the openings remain horizontally oriented while the nachos are being dipped into the dip or the sauce and cannot either slip or give way. In addition, the partition divides the inner chamber into two compartments. One of the compartments holds the nachos and nacho chips and the dip or sauce cup or cups and serves as a bowl while the nachos or nacho chips are being eaten. The other compartment can serve as a trash container for holding tear-off lids of the dip or sauce cups.

Such packages are normally made from cardboard; suitable blanks are stamped out and then the boxes are finished by folding the blanks and gluing them.

SUMMARY

Based on this, it is the object of the disclosure to improve a box of the type defined at the outset, in particular for use as a nacho package, so that the at least one closure flap can be securely locked in its closed position without impairing the aesthetic appearance of the box or package and without an additional step or action other than introducing the tuck-in tab.

This object is attained according to the disclosure in that on the partition, a hook-like projection is provided which, during the closing the closure flap and the introduction of the tuck-in tab into the inner chamber, automatically enters a through opening in the tuck-in tab, engages the tuck-in tab and keeps the closure flap in a locked state.

The disclosure is based on the concept of automatically locking the closure flap to the partition while the tuck-in tab is being introduced into the inner chamber, by means of the engagement of the hook-like projection of the inner partition with the opening of the tuck-in tab. Thus the partition is used not only for stabilizing the erected box and/or for subdividing the inner chamber, but moreover also serves to firmly hold or lock the closure flap in the closed position, so that the closure flap cannot open unintentionally as a result of a force exerted by the contents inside the box. Furthermore, in the engagement state, a secure hold of the hook-like projection in the opening is ensured, because the opening penetrates the tuck-in tab and therefore is bounded on all sides by an endless periphery or by the cardboard of the box blank respectively, and because the hook-like projection extends through the opening and catches on the periphery of the opening, so that even from major forces or deformation it is not moved out of engagement.

The cooperating engagement means formed by the hook-like projection and the opening are preferably located in such a way on the partition and on the tuck-in tab or the closure flap respectively that the hook-like projection, upon the introduction of the tuck-in tab into the inner chamber of the box, automatically enters into the opening of the tuck-in tab and catches in it, and the closure flap is locked or firmly held only after it has moved into the fully closed position.

Advantageously, the hook-like projection defines a plane parallel to the partition and to the second side walls. As a result, it is perpendicular to a plane defined by the opening in the tuck-in tab, which facilitates its introduction into the opening and secure catching in the opening. Preferably, the projection is located in the plane of the partition and is stamped out of the partition.

A further advantageous feature of the disclosure provides that the opening is stamped out of the tuck-in tab and has an endless periphery; that is, it is surrounded on all sides by the tuck-in tab or by the tuck-in tab and the remainder of the closure flap.

Advantageously, the hook-like projection and the opening are stamped out in the process of stamping out the box blank.

Expediently, the length of the opening in the introduction direction of the tuck-in tab is greater than the dimensions of the projection in the same direction, so that the projection can enter all the way into the opening. Advantageously, the projection also tapers counter to a direction of motion in which the tuck-in tab upon entering the hook-like projection moves into the opening in the tuck-in tab. This likewise facilitates automatic locking of the closure flap upon closure thereof.

Advantageously, the hook-like projection protrudes into a recess, open toward the closure flap, that is at least partially stamped out of the partition and that when the closure flap is closed receives the tuck-in tab entirely; the hook-like projection protrudes from one side into the opening in the tuck-in tab. The recess in the partition can be defined along its entire circumference by the partition, but preferably along a portion of its circumference it is defined by the one of the two first side walls that is adjacent to the tuck-in tab.

To facilitate the introduction of the tuck-in tab into the inner chamber or into the recess that is open toward the closure flap, a further preferred embodiment of the disclosure provides that the recess, on its side facing toward the closure flap, is defined by a guide ramp for the front edge of the tuck-in tab that points in the direction of motion, and/or tapers in the direction of motion of the tuck-in tab, in order to steer the tuck-in tab into the inner chamber or into the recess and beyond the hook-like projection.

On the far side of the hook-like projection, the recess expediently widens again, so that the tuck-in tab when fully inserted into the inner chamber of the box can be pivoted by a limited amount about a fold line that is located between the tuck-in tab and the remainder of the closure flap, in order to disengage the cooperating engagement means, if needed, from their mutual engagement.

However, this is not necessary if the closure flap is to remain permanently closed, as for example in the case of the nacho packages described above, whose contents, once the part of the upper side wall that can be torn open is torn open, can be removed through the thus-formed removal opening.

To facilitate the penetration of the hook-like projection into the opening of the tuck-in tab, the recess is defined in the introduction direction of the tuck-in tab on the far side of the hook-like projection by at least one peripheral edge that is inclined obliquely relative to the introduction direction, which peripheral edge deflects the front edge of the tuck-in tab behind the projection in such a way in the direction of the projection that the projection moves by itself into the opening in the tuck-in tab. The obliquely inclined peripheral edge or edges also ensure that the tuck-in tab cannot move again by itself into a position in which the hook-like projection is released from the opening.

To ensure a secure catching of the hook-like projection in the opening, the projection can be defined expediently, on its side facing away from the closure flap, by an edge which is inclined at an acute angle relative to a plane of the closed closure flap. Since the closed closure flap, as a consequence of deformation upon closure, is under a certain tension, the periphery of the opening adjacent to the projection is pulled against that edge. The inclination of the edge then also contributes to the fact that the tuck-in tab cannot move back again on its own into a position where the hook-like projection is released from the opening.

In order to improve the stability of the cooperating engagement means as much as possible, on the one hand the hook-like projection should be as broad as possible, and on the other hand, the spacing of the opening from the leading front edge of the tuck-in tab should be as great as possible. To achieve this, the opening advantageously extends as far as to a fold line that is located between the tuck-in tab and the remainder of the closure flap, or at least as far as into the immediate vicinity of this fold line.

To reduce the space needed for shipping or storage of the empty boxes as much as possible, the box can preferably be folded flat, in which state all the side walls, the partition, and the at least closure flap are generally oriented parallel to one another, and the cooperating engagement means are laterally offset from one another.

Advantageously, the box of the disclosure comprises a single blank, which makes it more economical to produce. The side of the box opposite the closure flap can advantageously be provided with an auto bottom that automatically closes the inner chamber on this side when the box is erected. Alternatively, a further closure flap and tuck-in tab can be provided there. In the latter case, cooperating engagement means can also be present on this side on the partition and on the further tuck-in tab; upon the introduction of the further tuck-in tab into the inner chamber they automatically enter into engagement with one another and thereafter securely and firmly hold the closure flap in the closed state, as described above. However, it is also possible to provide the cooperating engagement means on the partition and on the tuck-in tab on only one side of the box.

The box of the disclosure can especially advantageously be used as a tear-open package for nachos or nacho chips and at least one dip or sauce cup, since in such packages, the at least one closure flap, once closed, does not need to be opened again.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in further detail hereinafter in terms of an exemplary embodiment shown in the drawings.

FIG. 1 shows a perspective view of a box of the disclosure that serves as a package for nachos or nacho chips and two dip or sauce cups that is capable of being torn open.

FIG. 2 shows another perspective view of the package.

FIG. 3 shows a view from one side of the box with an opened closure flap.

FIG. 4 shows a view of the same side with the closure flap closed.

FIG. 5 shows a view of the opposite side with an automatic base.

FIG. 6 shows a sectional view along the line VI-VI of FIG. 1.

FIG. 7 shows a sectional view corresponding to FIG. 6, but while the box is being erected.

FIG. 8 shows an enlarged perspective view of a portion of an upper side wall and an inner partition with a hook-like projection for firmly holding the closed closure flap.

FIG. 9a shows an enlarged side view of parts of the inner partition with the hook-like projection as well as the closure flap prior to the introduction of a tuck-in tab of the closure flap into the inner chamber of the box.

FIG. 9b shows a corresponding view to FIG. 9a , but while the tuck-in tab is being introduced into the inner chamber.

FIG. 9c shows a corresponding view to FIG. 9b , but in a further stage.

FIG. 9d shows a corresponding view to FIG. 9c , but after the tuck-in tab has been fully introduced into the inner chamber and the closure flap has been locked.

FIG. 10 shows a blank for producing the box.

FIG. 11 shows the blank in a state that is partly folded up and glued together.

FIG. 12 shows the blank in a completely folded together and glued state.

DETAILED DESCRIPTION OF THE DISCLOSURE

The box 10 shown in the drawing forms a practical disposable tear-open package for nachos or nacho chips and for two dip or sauce cups (not shown), which are intended for consumption in movie theaters or at large public events.

The box 10 comprises a single blank 12 of cardboard, as shown in FIG. 10. The box 10 can be folded up flat for shipping and storage, as shown in FIG. 12, and is erected before use, in order to fill it with a bag of nachos or nacho chips as well as the two dip or sauce cups. After the filled box 10 has been sold, it is torn open by the customer at the top before consumption, in order to remove the dip or sauce cups and insert them into two openings made in the top of the box 10. After the bag with the nachos or nacho chips has been opened, in order for them to be consumed the latter can either be taken out of the bag, or the bag can be emptied into the opened box 10, so that then the nachos or nacho chips can be taken out one at a time by hand, so that they can be dipped into the opened dip or sauce cups and then consumed.

As shown in FIGS. 1 and 2, the box 10 in the erected state has a cuboid shape. The box 10 essentially comprises two opposed plane, parallel and congruent first outer side walls 16, 18, which form the wide sides of the box 10; two opposed plane, parallel and congruent second outer side walls 20, 22, which form two narrow sides of the box 10 and are oriented perpendicular to the first side walls 16, 18; two plane third outer side walls 24, 26, which form the other two narrow sides of the box 10 and are oriented perpendicular to the first and second side walls 16, 18, 20, 22; and one plane inner partition 30, which is oriented at a distance from and parallel to the two second side walls 20, 22 and perpendicular to the two third side walls 24, 26 and extends between the two first side walls 16, 18.

The side walls 16, 18, 20, 22, 24, 26 define an inner chamber 32, which is divided by the partition 30 into two compartments 34, 36. The compartment 34 serves to receive the bag with the nachos or nacho chips as well as the two dip or sauce cups and can be used during consumption as a bowl for nachos or nacho chips. The compartment 36 serves as a trash container for the removable closure cap of the dip or sauce cups.

One of the two first side walls 16, 18, in use, forms the top side of the box 10. This side wall 16 has a tear-off part 40, which is separated by a perforation line 38 from the remainder of the side wall 16 and occupies somewhat more than half the side wall 16 and can be torn open to open the box 10. The side wall 16 is furthermore provided with three openings 42, 44, 46, of which one, 42, is oval in shape and serves as a finger opening for grasping and tearing off the tear-off part 40. Two further openings 44, 46 are round and allow the dip or sauce cups to be inserted into them. The two round openings 44, 46 are each surrounded by eight radial notches and one circular outer fold line. The notches and the fold line together with the inner periphery of the openings 44, 46 define eight circular-annular segments, which upon insertion of the dip or sauce cups are bent downward along the fold line into the second compartment 36. In the drawing, one further optional opening 48 is also shown, which can serve for throwing away the tear-off lid of the dip or sauce cups into the second compartment 36.

The other first side wall 18 forms the underside of the box 10 and has no openings. The two second side walls 20, 22 join two opposed edges of the two first side walls 16, 18.

Of the two third side walls 24, 26, one, 24, is embodied as an auto bottom 50 (FIG. 1), which upon erection of the box 10 closes automatically and closes the inner chamber 32 on this side. The auto bottom 50 has a known construction, as shown in the drawing, and therefore needs no further description.

The opposed third side wall 26 is embodied as a closure flap 54 (FIG. 2) and is pivotably joined to the first side wall 18 that forms the underside of the box 10. Between this side wall 18 and the closure flap 54, there is a fold line 56, about which the closure flap 54 can be pivoted relative to the side wall 18. The closure flap 54 is provided with a plane tuck-in tab 58, which extends over the entire width of the closure flap 54. The tuck-in tab 58 is joined, along a fold line 60 parallel to the fold line 56, to the remainder of the closure flap 54 and upon closure of the closure flap 54 it is introduced all the way into the inner chamber 32.

To prevent the tuck-in tab 58 introduced into the inner chamber 32 from hindering the insertion of a dip or sauce cup into the adjacent opening 44, the free edge 62 of the tuck-in tab 58, which edge is parallel to the fold lines 56, 60, is provided opposite the opening 44 with a flat circular, segmental indentation 63. To make it easier to introduce the tuck-in tab 58 into the inner chamber 32, the opposed lateral ends of the tuck-in tab 58 are rounded, so that the tuck-in tab 58 tapers toward the peripheral edge.

As best shown in FIG. 6, the height of the inner partition 30 is equivalent to the height of the two second side walls 20, 22. As shown in FIGS. 6 and 11, the inner partition 30 is firmly connected to the side wall 16 between the oval opening 42 and the other openings 44, 46, 48. For that purpose, the partition 30 is provided with a narrow, protruding adhesive tab 64 on one of the ends of the blank 12, which tab is firmly glued to the inside of the side wall 16.

As best shown in FIG. 11, the partition 30 is joined to the remainder of the blank 12, or to the side wall 16, by two portions 68, 70 of the blank 12. The first portion 68, adjacent to the partition 30, has a width in the direction of the longitudinal axis of the blank 12 that is equivalent to the width of the second compartment 36 and rests on the bottom of the second compartment 36 against the inside of the side wall 18, which forms the underside of the box 10. The second portion 70, adjacent to the side wall 16, has a width in the direction of the longitudinal axis of the blank 12 that is equivalent to the height of the side walls 20, 22 and rests against the inside of the side wall 22 that forms the adjacent narrow side of the box 10. The inside of the side wall 22 is glued on its upper end to the second portion 70 along a narrow strip 69.

Between the adhesive tab 65 and the partition 30, between the partition 30 and the first portion 68, and between the second portion 70 and the side wall 16, fold lines 72 are provided, which permit pivoting the inner partition 30 relative to the two side walls 16, 18, as shown in FIG. 7. Also between the first and second portions 68, 70 and between the respective adjacent side walls 16, 20; 20, 18; 18, 22, there are fold lines 72. All the fold lines 72 are parallel to one another.

By means of the described arrangement, the partition 30, once the box 10 is erected, is automatically aligned in parallel to the two side walls 20, 22, while when the box 10 is folded flat the partition is oriented in parallel to the two side walls 16, 18. In the folded-flat state of the box 10, as shown in FIG. 12, the two side walls 20, 22, all the parts of the auto bottom 50, and the closure flap 54 along with the tuck-in tab 58 are also oriented parallel to the side walls 16, 18.

In order to ensure that the partition 30, as the box 10 is being erected, does not hinder the closure of the automatic base 50, a triangular part 74 of the partition 30 is joined, on its face end adjacent to the auto bottom 50, along an oblique fold line 76, to the remainder of the partition 30 in such a way that it can move away from an adjacent part of the automatic base 50 when the latter, as the box 10 is being erected, shifts laterally relative to the partition 30. As can be seen from FIG. 11, the partition 30 is furthermore somewhat shorter on this side, so that it does not extend all the way to a straight fold line 77 between the side walls 16, 18 and the auto bottom 50, while on the opposite side it extends as far as the fold line 56.

To prevent the folded-flat box 10 from being thicker than desired in the overlapping region of the automatic base 50, the two portions 68, 70 have smaller dimensions transversely to the longitudinal axis of the blank 12 than the side walls 16, 18, 20, 22, so that there, on the bottom of the compartment 36 and on the inside of the side wall 22, no further layer of cardboard formed by the portions 68, 70 is present.

As best shown in FIGS. 10 through 12, between the tuck-in tab 58 and the remainder of the closure flap 54, the fold line 56 is provided with two short notches 78 on both ends. Next to the closure flap 54, protruding tabs 80, 82 opposite one another are provided on the two side walls 20, 22; before the closure flap 54 is closed, these tabs are pivoted from opposite sides to a position in front of the opening of the inner chamber 32 adjacent to the closure flap 54. The two tabs 80, 82 are provided in a known manner with small lateral projections 84, which upon closure of the closure flap 54 enter into the notches 78 and are intended to keep the closure flap 54 in the closed position.

However, if the customer holds the box 10 in such a way that the closure flap 54 is oriented downward and the entire weight of the nachos or nacho chips and the two dip or sauce cups rests upon the inside of the closure flap 54, both projections 84 may slip out of the associated notches 78. As a consequence, the closure flap 54 opens and the contents of the box 10 fall out onto the floor.

To avoid this, the tuck-in tab 58 and a peripheral edge 86, of the partition 30 that faces the closure flap 54, are provided with cooperating engagement means, which upon the introduction of the tuck-in tab 58 into the inner chamber 32, during the closure of the closure flap 54, automatically enter into engagement with one another and securely hold the closure flap 54 thereafter in the closed state.

As best shown in FIGS. 3, 9 a through 9 d and 10 through 12, the engagement means of the tuck-in tab 58 comprise an opening 88, which is stamped out of the tuck-in tab 58 and penetrates the tuck-in tab and which is bounded on all sides by an endless peripheral rim or by the cardboard of the closure flap 54. The plane defined by the opening 88 is located in the plane of the tuck-in tab 58. The endless peripheral rim of the opening 88 comprises a straight peripheral rim portion extending along the fold line 56 and a U-shaped peripheral rim portion, the legs of which extend as far as to the fold line 56, and whose curved base is spaced apart from the fold line 56. The straight peripheral rim portion of the opening 88 could, however, also be located inside the tuck-in tab 58.

As best shown in FIGS. 8 and 9 a through 9 d, the engagement means of the partition 30 include a hook-like projection 90, which upon closure of the closure flap 54 automatically enters into the opening 88 of the tuck-in tab 58 and there engages with the peripheral rim of the opening 88, as a result of which it firmly keeps the closure flap 54 in the closed position.

The hook-like projection 90 is an integral part of the partition 30; it protrudes in the plane of the partition 30 into a recess 92 that is stamped out of the partition 30 in the process of stamping the blank 12 and that is open toward the closure flap 54, which recess receives the tuck-in tab 58 when the closure flap 54 is closed. As a result, the projection 90 is located in a plane parallel to the partition 30 and to the second side walls 20, 22, which plane is oriented perpendicular to the plane of the tuck-in tab 58 and to the plane of the closure flap 54, which makes the insertion of the projection 90 into the opening 88 and its catching in the opening 88 easier.

As best shown in FIG. 8, the recess 92 is located in the periphery 86 of the partition 30 in the vicinity of the side wall 16 in such a way that it is bounded partly by the partition 30 and partly by the side wall 16. On its side that faces toward the closure flap 54, the hook-like projection 90 protruding into the recess 92 is defined by an edge 94, which is inclined obliquely to the side wall 16 and together with it, in the direction of motion of the tuck-in tab 58 upon its introduction into the inner chamber 32, defines a tapered wedge-like part of the recess 92. Upon closure of the closure flap 54 the oblique edge 94 serves as a guide ramp for the front edge 96 of the tuck-in tab 58, in order to steer the tuck-in tab past the projection 90, as shown in FIG. 9 a.

Toward the adjacent side wall 16, the hook-like projection 90 is bounded by an upper edge 98, which is oriented generally parallel to the side wall 16 and is slightly spaced apart from it, so that upon closure of the closure flap 54, the front edge 96 of the tuck-in tab 58 automatically moves between the upper edge 98 and the side wall 16, as shown in FIG. 9 b.

On the far side of the projection 90, the recess 92 is defined toward the side wall 16 by two edges 100, 102 located one behind the other, which with the side wall 16 form an increasingly larger acute angle. The two edges 100, 102 serve to deflect the front edge 96 of the tuck-in tab 58, after it passes the projection 90, away from the side wall 16, so that the projection 90 moves increasingly farther into the opening 88, as shown in FIG. 9 c.

Once the tuck-in tab 58 is located entirely in the inner chamber 32 of the box 10, as shown in FIG. 9d , it is held by the oblique edge 102 in a position in which the hook-like projection 90 protrudes through the opening 88 in the tuck-in tab 58 and, as a result of a force exerted from inside on the closure flap 54, can no longer be released from the opening 88.

On its side facing away from the closure flap 54, the projection 90 is defined by an oblique edge 104, which is inclined in the same direction as the oblique edge 94, but at a steeper angle of inclination. This likewise contributes to the firm hold of the tuck-in tab 58 on the projection 90 when a force is exerted from the inside on the closure flap 54.

In the folded-flat state of the box 10, as shown in FIG. 12, the side walls 16, 18, 20, 22, 24, 26 as well as the partition 30 are oriented generally parallel to one another and lie flat one above the other. In this state, the cooperating engagement means, that is, the opening 88 and the hook-like projection 90, are offset laterally from one another.

Although certain embodiments have been described herein in accordance with the teachings of the present disclosure, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the disclosure that fairly fall within the scope of permissible equivalents. 

What is claimed is:
 1. A packaging box made of a folded blank of cardboard, having two spaced apart first side walls on opposed first sides of the box, two spaced apart second side walls on opposed second sides of the box and joining the two first side walls, at least one closure flap for closing an inner chamber defined by the first and second side walls on a third side of the box, which closure flap is pivotably joined to one of the two first side walls and has a tuck-in tab that can be introduced into the inner chamber in the vicinity of the other one of the two first side walls, and an inner partition spaced apart from and in parallel to the second side walls, wherein a hook-like projection on the partition, during the closing of the closure flap and the introduction of the tuck-in tab into the inner chamber, automatically enters a through opening in the tuck-in tab, engages the tuck-in tab and keeps the closure flap in a locked state.
 2. The packaging box of claim 1, wherein the opening is stamped out of the tuck-in tab and is surrounded on all sides by the tuck-in tab or by the tuck-in tab and the remainder of the closure flap.
 3. The packaging box of claim 1, wherein the hook-like projection defines a plane that is parallel to the partition and to the second side walls, which plane is perpendicular to a plane defined by the tuck-in tab.
 4. The packaging box of claim 1, wherein the hook-like projection is stamped out of the partition.
 5. The packaging box of claim 1, wherein the hook-like projection protrudes into a recess, which is stamped out from the partition, is open toward the closure flap and receives the tuck-in tab when the closure flap is closed.
 6. The packaging box of claim 5, wherein the recess is defined at least partially by the other one of the two first side walls.
 7. The packaging box of claim 5, wherein the recess, on its side facing toward the closure flap, tapers in the direction of motion of the tuck-in tab during its introduction into the inner chamber.
 8. The packaging box of claim 5, wherein in the direction of motion of the tuck-in tab during its introduction into the inner chamber the recess widens on the far side of the projection.
 9. The packaging box of claim 5, wherein in the direction of motion of the tuck-in tab during its introduction into the inner chamber the recess is defined on the far side of the projection by at least one peripheral edge, which deflects a front edge of the tuck-in tab in the direction of the projection, so that the projection automatically enters into the opening in the tuck-in tab.
 10. The packaging box of claim 1, wherein the opening extends as far as to a fold line between the tuck-in tab and a remainder of the closure flap, or as far as into the vicinity of the fold line.
 11. The packaging box of claim 1, wherein the opening has a U-shaped cross section.
 12. The packaging box of claim 1, wherein the box can be folded flat, a state in which all the side walls, the partition and the at least one closure flap are oriented generally parallel to one another, and in which the hook-like projection and the opening are laterally offset from one another.
 13. The packaging box of claim 1, wherein the box is made of a single blank of cardboard, and wherein the hook-like projection and the opening are stamped out of the single blank.
 14. The packaging box of claim 1, wherein an auto bottom is located on the side of the box opposite from the closure flap.
 15. The packaging box of claim 1, wherein a further closure flap is located on the side of the box opposite from the closure flap. 